[PATCH] D72361: [DAGCombiner] reduce extract subvector of concat

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon accepted this revision.
RKSimon added a comment.
This revision is now accepted and ready to land.

LGTM - some of NFC refactoring as pre-commits would make sense to separate it from the new features.



================
Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:18576
+    unsigned ExtNumElts = NVT.getVectorNumElements();
+    assert(ExtIdx % ExtNumElts == 0 &&
+           "Extract index is not a multiple of the input vector length.");
----------------
If we're peeking into any concat can we guarantee this or should we just wrap in an if() instead?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D72361/new/

https://reviews.llvm.org/D72361